from my understanding, tw is just a way to customize the skin which is actually the "frame" param. and the "frame" is a gif or jpg (as i undestand it from my ptviewer knowldeg)
but tw outputs a config file that contains the name of each scene, the description, the jpg name, etc. if you teach your client to replace the names on the config file, then yes he can. and then he has save and upload that file.